570 



THE URINE 



[CH. XXXVII. 



CHEMICAL SEDIMENTS IN URINE Continued. 

 IN ACID URINE. IN ALKALINE URINE. 



called envelope crystals. Insoluble in 

 acetic acid. 



Cystin. Hexagonal plates. Rare. 



Leucine and Tyrosine. Rare. 



Calcium Phosphate, 



CaHPO 4 + 2H 2 O. Rare. 



All the preceding are soluble in acetic 

 acid without effervescence. 



Calcium Carbonate, CaCO ;} . Biscuit- 

 shaped crystals. Soluble in acetic acid 

 with effervescence. 



Ammonium Urate, 



C 5 H 2 (NH 4 ),.N 4 O ; ,. "Thorn-apple" 

 spherules. 



Leucine and Tyrosine. Very rare. 



PATHOLOGICAL URINE. 



Under this head we shall briefly consider only those abnormal 



constituents which are most frequently met with. 



Proteids. There is no proteid matter in normal urine,* and the 



most common cause of the appearance of albumin in the urine is 

 disease of the kidney (Bright's disease). The term 

 "albumin" is the one used by clinical observers. 

 Properly speaking, it is a mixture of serum albumin 

 and serum globulin. Of these, serum albumin is 

 usually the more abundant. Globulins, and especi- 

 ally englobulins, have probably larger molecules, so 

 escape of globulin indicates more serious damage to 

 the renal cells. The best methods of testing for 

 and estimating the proteid are the following: 



(a) Boil the top of a long column of urine in a test-tube. 

 If the urine is acid, the albumin is coagulated. If the quantity 

 of albumin is small, the cloudiness produced is readily seen, 

 as the unboiled urine below it is clear. This is insoluble in a 

 few drops of acetic acid, and so may be distinguished from 

 phosphates. If the urine is alkaline, it should be first rendered 

 acid with a little dilute acetic acid. 



(/>) Heller's Nitric-acid Test. Pour some of the urine gently 

 on to the surface of some nitric acid in a test-tube. A ring of 

 white precipitate occurs at the junction of the two liquids. This 

 test is used for small quantities of albumin. 



(c) Estimation of Albumin by E shack's Albuminometer. 

 Esbach's reagent for precipitating the albumin is made by 

 dissolving 10 grammes of picric acid and 20 grammes of citric 

 acid in 800 or 900 c.c. of boiling water, and then adding sufficient water to make up 

 toalitre(1000c.c.). 



The albuminometer is a test-tube graduated as shown in fig. 435. 

 Pour the urine into the tube up to the mark U ; then the reagent up to the 

 mark R. Close the tube with a cork, and to ensure complete mixture, tilt it to and 



FIG. 435. Esbach's 

 Albumiuometer. 



* This absolute statement is true for all practical purposes. Morner, however, 

 has stated that a trace of proteid matter (serum albumin plus the proteid 

 constituent of mucin) does occur in normal urine ; but the trace is negligible, 

 many hundreds of litres of urine having to be used to obtain an appreciable 

 quantity. 



